1. Field of the Invention
The present invention relates to a vibration attenuating and sound suppressing steel material useful for panels, ducts, automobiles, trains and electrical appliance and other structural members which produce vibrations and sounds.
2. Description of Prior Art
In recent years, traffic sounds and plant sounds have been treated as a social problem of public pollution, various sound preventive devices and equipments such as sound suppressing walls have been proposed and actually in service from view points of sound absorption and sound shielding.
Further, in case where sounds are radiated by the vibration of the structure itself, sound prevention means have been proposed by applying anti-vibration treatments to the steel structure such as coating of anti-vibration paint, rubber and plastics, for example.
On the other hand, some materials, such as manganese-copper alloys and flake-graphite cast iron have been proposed for providing anti-vibration property to the structural components themselves. However, the manganese-copper alloys have a defect that their anti-vibration function deteriorates at temperatures 500.degree. C or higher, and their workability and weldability are poor. Also the flake-graphite cast iron has a very poor workability and weldability.
Vibration attenuating or damping alloys have been developed and disclosed, for example in Japanese Patent Publications Sho 52-803, Sho 52-804 and Sho 52-1683, but these alloys are also confronted with the problems of poor workability and weldability as well as high production cost due to a large amount of special alloy elements such as Cr and Al used.